1. Field of the Invention
The present invention relates to spinal fixation devices and, in particular, to cross-connectors for connecting spinal fixation devices, such as spinal rods that are attached onto a patient's spine.
2. Background Information
There are many medical situations, because of disease, injury or deformity, where it is necessary to align and/or fix a desired relationship between adjacent vertebral bodies. In order to accomplish this goal, orthopedic spinal surgeons utilize spinal fixation devices to provide the desired relationship between adjacent vertebral bodies. Such spinal fixation devices typically include a spinal fixation element, such as a relatively rigid fixation rod, that is connected to adjacent vertebrae by attaching the rod to anchor devices implanted into the vertebrae.
Often, the spinal fixation rods are placed on opposite sides of the spinous process in a substantially parallel relationship. These spinal fixation rods may have pre-determined contours according to properties of the target implantation site. Once installed, the spinal fixation rods hold the vertebrae in a desired spatial relationship.
It may also be necessary in some circumstances to provide a spinal cross-connector at one or more points between the two spinal fixation rods in order to provide additional stability to the structure. Particularly, adjacent spinal fixation rod assemblies can be made more robust by using a cross-connector to bridge the pair of spinal rods.
While current spinal cross-connectors are effective, problems exist such as in mounting and maintaining the cross-connectors in a desired position and orientation with respect to the spinal rods. Other problems also exist with current cross-connectors such as sizing and locking issues. Moreover, current spinal cross-connectors do not allow room for extensor muscles of the spine. Particularly, the current spinal cross-connectors tend to constrict the spinal extensor muscles.
Accordingly, there presently exists a need for a spinal cross-connector that, when installed, provides allowance for spinal extensor muscles.
Moreover, there presently exists a need for a spinal cross-connector that, when installed, does not constrict spinal extensor muscles and/or allow the intrusion of the extensor muscles into the spinal cord space.